Centralizing drill



L. E. GRAY ETAL Nov. 27, 1951 CENTRALIIZING DRILL Filed Sept. 21, 1948 E. Gray arm Cczr/ Web/"oak ATTOR N EV Patented Nov. 27,1951

\ UNIT E D S TAT E S PAT ENT F Fl CE.

CE NTRALIZING' 1mm.

Lawrence E. Gray and Carl H. Viebrock, Douglas, Wash.

Application September 21, 1948, Serial No. 50,386

1 Claim. 1

This invention relates to a drill, and more particularly to an attachment for guiding a drill in the removal of rivets.

The object of the invention is to provide an attachment for a drill that will facilitate the drilling of a rivet or bolt when it is desired to remove the latter.

Another object or the invention is to provide an attachment for a drill that will guide the drill onto a rivet to be removed, and will also facilitate the retraction of the drill after the rivet has been removed.

A further object of the invention is to provide a drill attachment which is extremely simple and inexpensive to manufacture.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings forming a part of this application, and in which like numerals are employed to designate like parts throughout the same:

Figure 1 is a side elevational view of the drill attachment according to the present invention;

Figure 2 is a sectional view taken on the line 22 of Figure 1;

Figure 3 is an end elevational view of the device;

Figure 4 is a sectional view taken on line 4-4 of Figure 2;

Figure 5 is a sectional view taken on the line 5-5 of Figure 2;

Figure 6 is a sectional View taken on the line 6-6 of Figure 2;

Figure 7 is a fragmentary elevational view showing the blank for forming the outer casing.

Referring in detail to the drawings, the numeral l9 designates a drill which is driven by a motor H (broken lines). The attachment for the drill l0 comprises an open-ended, knurled socket l2 which has its exterior tapered, as at 13. The interior of the socket 12 has a recess M of polygonal cross sectional contour extending inwardly from one end thereof and is also provided with a plurality oi longitudinally-extending, spaced grooves I5. An open-ended, knurled casing I 6 is arranged in end-to-end relation with respect to the socket l2, and the casing I6 is provided on one end with a shoulder I! having an external cross sectional contour and size to fit snugly in the recess 14 of the socket.

A bronze bearing l8 encircles and is press fitted, or otherwise secured, to the drill l0 and slidably projects through the sleeve I! at the other open end of the casing l6, and slidably positioned over the bearing l8 and encased within the casing i5 is a steel reduced sleeve extension or hearing IS. A washer 20 abuts the bearing l8 and surrounds the drill l0, and is slidably arranged in the casing [6. A coil spring 2| is circumposed on the drill H] and is interposed between the washer 2B and shoulder I! for normally biasing the drill away from the socket 12 when pressure on the drill is released. In assembling the drill attachment, the casing I6 is first fabricated with an upstanding rim 22, Figure 'I, to provide sufficient clearance for the insertion of the elements into the interior of the easing. Then, the rim 22 is bent along the crease line 9 to provide the inwardly-extending flange 23, Figure 2, to thereby maintain the device in assembled relation.

The socket E2 is a type commonly used by automobile mechanics. It is to be stated that it is one whereby substitution of different sizes can readily be made to allow for variations of nuts, bolts and rivets.

In use, when it is desired to remove a rivet 24, for example, from a work piece 25, the socket I2 is arranged so that its lower end embraces the head of the rivet. Then, upon application of pressure on the motor H, the bearing l8 will be moved inwardly in the casing It at the same time that the drill I0 is moved through the socket l2 and into engagement with the rivet 24. After the head of the rivet 24 has been drilled away, the rivet 24 can be easily pushed out through the work piece 25 and when the pressure on the drill is released, then the spring 2! will move the washer 29, bearing l8, motor II and drill l0 away from the work piece 25.

By means of the attachment, the drill may also be used for removing stove bolts that are rusted, removing carriage bolts from a hood, and can be adapted for many diflerent trades.

As many embodiments may be made of this inventive concept, and as many modifications may be made in the embodiment hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

We claim:

In a tool of the class described, a tubular casing having a lower reduced end portion and an annular flange inturned at its upper end, a drill extending axially through said casing and projecting beyond said reduced end portion, a bearing sleeve encircling said drill and positioned within the upper end of said casing in contact with said flange, a washer within said casing and encircling said drill, a coiled spring within said casing and encircling said drill and having ts lower end seated on the shoulder formed by the said reduced end portion and its upper end bearing against said washer, a second bearing sleeve encircling and secured to the drill, said second bearing sleeve being seated in the first bearing sleeve and seated on said washer, and a centering member having an axial passage therethrough of the same cross sectional contour as and tightly receiving said reduced end portion on which it 10 REFERENCES CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS Number Name Date 2,294,303 Jagow Aug. 25. 1942 2,296,087 Burns Sept. 15. 1942 

